The invention relates to a display device comprising a cathode-ray tube with an envelope formed by a display window, a neck and a funnel-shaped portion which connects the display window to the neck. A deflection unit is mounted on the envelope at the area of the transition from the neck to the funnel-shaped portion of the envelope by elements for connecting the deflection unit to the envelope.
The invention further relates to a cathode-ray tube and a deflection unit for use in such a display device.
U.S. Pat. No. 3,986,156 describes such a display device in which an annular platform is attached onto the envelope of the cathode-ray tube and the deflection unit is provided with a housing. Between the deflection unit and the platform there are rigid elements which interconnect the housing of the deflection unit and the platform. Once the position of the deflection unit has been adjusted the rigid elements are fixed in their position to the deflection unit and the platform, for example, by means of ultrasonic welding. The adjusting of the position of the deflection unit relative to the envelope is attained by handling the deflection unit, so that an optimum position relative to the envelope is obtained. Whilst the deflection unit is handled the rigid elements are under no load. Subsequently, the rigid elements are secured to the deflection unit and the envelope by means of an adhesive, such that the adjusted position is fixed.
When the deflecton unit is released after the rigid elements have been fixed, these rigid elements are loaded suddenly, and the accurately adjusted positioning may be adversely affected. As a consequence hereof, the operation of the display device is also adversely affected.